| Club: | Portland Timbers |
| Season: | 2021 |
| Chrtitle: | President |
| Chairman: | Merritt Paulson |
| Mgrtitle: | Head coach |
| Manager: | Giovanni Savarese |
| Stadium: | Providence Park Portland, Oregon (Capacity: 25,218) |
| League: | Major League Soccer |
| League Result: | Conference: 4th Overall: 5th |
| Cup1: | MLS Cup Playoffs |
| Cup1 Result: | Runner-Up |
| Cup2: | U.S. Open Cup |
| Cup2 Result: | Canceled |
| Cup3: | Cascadia Cup |
| Cup3 Result: | 2nd |
| Cup4: | CONCACAF Champions League |
| Cup4 Result: | Quarter-finals |
| Largest Win: | League/All: POR 6–1 RSL (9/25, MLS) |
| Largest Loss: | League/All: SEA 6–2 POR (8/15) |
| American: | true |
| Pattern B1: | _timbers21H |
| Pattern Sh1: | _adidasshortgold |
| Pattern So1: | _timbers21H |
| Leftarm1: | 154821 |
| Body1: | 00382A |
| Rightarm1: | 154821 |
| Shorts1: | 154821 |
| Socks1: | 154821 |
| Pattern Name2: | Secondary |
| Pattern La2: | _timbers20a |
| Pattern B2: | _timbers20A |
| Pattern Ra2: | _timbers20a |
| Pattern So2: | _timbers20a |
| Leftarm2: | FFFFFF |
| Body2: | FFFFFF |
| Rightarm2: | FFFFFF |
| Shorts2: | FFFFFF |
| Socks2: | FFFFFF |
| Prevseason: | 2020 |
| Nextseason: | 2022 |
| Updated: | May 5, 2021 |
The 2021 Portland Timbers season was the club's 35th season of existence and the 11th season for the Portland Timbers in Major League Soccer (MLS), the top-flight professional soccer league in the United States and Canada. The season covers the period from the end of the Timber's last match in MLS or MLS Playoffs in 2020 (November 22, 2020) to their final match in MLS Cup Plays on December 11, 2021.
See also: 2020 Portland Timbers season.
The 2020 season was heavily altered due to the onset of the COVID-19 pandemic. Portland played its first two matches as scheduled, before the season was suspended on March 12, 2020. The season resumed with a bubble tournament near Orlando, Florida, dubbed the MLS is Back Tournament, which began on July 13, 2020, and concluded on August 11, 2020. Portland defeated Orlando City SC in the championship, and earned a berth into the 2021 CONCACAF Champions League for winning the tournament.
The league resumed, with Portland playing their remaining matches behind closed doors. The number of regular season matches from 2020 decreased from 34 to 23 due to the pandemic. Ultimately Portland finished with an 11–6–6 regular season record, and earned a berth into the 2020 MLS Cup Playoffs. Portland was defeated by FC Dallas in the opening round. Diego Valeri lead the team in MLS goals with six total, and Jeremy Ebobisse lead Portland in goals across all competitions with eight.
The season was postponed from the normal late February 27–28 starting weekend and instead began on the weekend of April 16–18 due to the pandemic. Ahead of the start of the regular season, Portland began competitive fixtures in the Champions League on April 6, 2021.
See main article: 2021 Major League Soccer season.
See main article: 2021 MLS Cup Playoffs.
See main article: MLS Cup 2021.
See main article: 2021 U.S. Open Cup.
See main article: 2021 CONCACAF Champions League.
Numbers in parentheses denote appearances as a substitute.
(T2) = Players called up from Portland Timbers 2 for short-term contracts.
The list is sorted by total minutes played then by jersey number.
The list is sorted by shirt number when total assists are equal.
The list is sorted by shirt number when total clean sheets are equal.
| Games played | 2 (2 Champions League) | |
| Games won | 1 (1 Champions League) | |
| Games drawn | 1 (1 Champions League) | |
| Games lost | 0 | |
| Goals scored | 7 (7 Champions League) | |
| Goals conceded | 2 (2 Champions League) | |
| Goal difference | +5 (+5 Champions League) | |
| Clean sheets | 1 (1 Champions League) | |
| Yellow cards | 3 (3 Champions League) | |
| Red cards | 0 | |
| Most appearances | Tied (2 appearances) | |
| Top scorer |  Yimmi Chará (3 goals) | |
| Top assists |  Josecarlos Van Rankin (2 assists) | |
| Top shutouts |  Steve Clark (1 shutout) | |
| Winning percentage | Overall: 1/2 (50%) |
The list is sorted by shirt number when total goals are equal.